The present invention relates to a crosslinkable organic polymer and a method for the preparation of a crosslinked organic polymer or, more particularly, to a method for the preparation of a crosslinked organic polymer from a crosslinkable organic polymer which can be cured by crosslink formation at an advantageously high velocity even in the core portion of a thick body without disadvantages due to the formation of a by-product in the crosslinking reaction.
It is known that various organic polymers can be imparted with improved properties by introducing crosslinkable groups into the molecular structure of the base polymer and bringing the thus obtained crosslinkable polymer under such conditions that the crosslinkable groups can pertain to the crosslinking reaction to form crosslinks between molecules. A variety of crosslinkable groups have been proposed in the prior art and several organic polymers can be crosslinked by utilizing organosilicon groups as the crosslinkable groups introduced into and bonded to the base polymer including an organosilicon group of the formula .tbd.SiX in an organosilane compound, in which X is a hydrolyzable group, so that, when the thus silane-modified polymer is exposed to a moisture-containing atmosphere, the hydrolyzable groups are hydrolyzed by the atmospheric moisture to form silanol groups followed by the intermolecular silanol condensation reaction to form crosslinks (see, for example, U.S. Pat. Nos. 3,632,557, 3,563,943, 3,471,440 and 3,971,751 and Japanese Patent Publication No. 48-1711).
Although such a silane-modified crosslinkable organic polymer is advantageous in respect of the crosslinkability thereof even at room temperature since the crosslinking reaction solely utilizes the hydrolysis by the atmospheric moisture, the velocity of the crosslinking reaction is relatively low so that a long time is sometimes taken before complete crosslink formation between the polymer molecules or the core portion of a thick body of the polymer is sometimes left uncrosslinked unless the base polymer has good permeability to atmospheric moisture. Further, the crosslinking reaction proceeds by the mechanism of a condensation reaction so that a by-product is always formed and contained in the body of the polymer to cause various adverse influences on the properties of the crosslinked polymer.